Improvement in niqldlnos



P. CONVER.

Improvement in Molding.

No. 130,900. Patented Aug. 27,1872.

WITNESSES. mvsmon I J m- UNITED STATES PATENT OFFICE.

PETER GONVER, or rAnMnieroN, ILLINOIS.

IMPROVEMENT ln-morniues.

Specification forming part of Letters Patent No. 130,900, dated August 27, 1872.

To all whom it may concern:

Be it known that I, PETER OONVER, of

Farmington, in the county of Fulton and State Figure l-of the drawing is a representation of a top view of my'invention. Fig. 2 is a sectional view, and Flg. 3 is a view, of my pattern.

This invention has relation to an improvement in' the preparation of sand-molds for casting articles of metal; and consists in the means herein after described for facilitating the withdrawal from the sand of the pattern without disturbing the mold.

My invention is specially applicable in the preparation of molds for small castings, of which a large quantity are cast in gates, and where the nature of the casting is such as to preclude the finishing of the mold after the withdrawal of the pattern.

Forthe purposes of my invention I provide a counterpart of the sand-mold of plaster of Paris, metal, or equivalent, as shown at A, which, for convenience of reference, I term a receiver. A designates a receiver for a toothed gear-wheel, the form of the pattern bein g sunken in the face. At B is a hole through the center of the receiver, and at b smaller holes, for a purpose hereinafter specified. I

construct the pattern D with a number of rods,

d, projecting from different parts of and at right angles to the face. The drag or first part of the mold I make in the ordinary way, and invert for the withdrawal of the pattern.

The rods will then rise above the surface, and will correspond in position to the holes b. I then lay upon the surface of the sand the re ceiver, face down, the rods and holes guiding it, and then insert a handle or other tool, E, through the hole B and catch the pattern, which may have a hole in the center or be otherwise adapted to the reception of said handle. I then gently raise the pattern into the recess of the receiver, and afterward remove both pattern and receiver.

By this method I am enabled to. produce a sharp. exact impression of the pattern, which may be of the proper form, and not constructed with a taper or draw, to enable it to be removed without disturbing the upper edges of the sand-walls.

Where hollow castings are to be made I place on the bottom of the pattern several strips of tin, and after the sand is packed insert therods d in holes, as before described, and remove the pattern, according to the method detailed. Afterward the tin may be easily removed.

When the receiver is made of plaster or other frail material the holes I) should be lined with metal to prevent them from losing shape.

What I claim as new is- The combination, with a pattern having guide-rods d, of a receiver, A, provided with a recess corresponding in form to the pattern, and with perforations for the passage of the guiderods, substantially as specified.

In testimony that I claim the above I have hereunto subscribed my name in the presence of two witnesses.

PETER GONVER.

Witnesses:

GEO. H. LITTLEWOOD, ELIAS Po'r'rnn. 

